# Atmel EDBG-based Tools Protocols
Serial trace commands

### Signon

Used to check that serial trace is supoorted by the hardware.

Table 27. Signon

Field | Size | Description
--- | --- | ---
SERIAL_TRACE | 1 byte | 0x87
SIGNON | 1 byte | 0x0F

Response:

Table 28. Signon response

Field | Size | Description
--- | --- | ---
SERIAL_TRACE | 1 byte | 0x87
SIGNON | 1 byte | 0x0F
Signon string | 3 bytes | "OK\0"

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